Structural alignment in dialogue and monologue (and what attention may have to do with it)

In the Interactive Alignment Theory, alignment is promoted by dialogic features on a dialogue-monologue continuum. More alignment in prototypical dialogue (a chat among friends) than in prototypical monologue (a lecture) seems plausible, but the role of other dialogic features for alignment is less clear. The current study tests the joint influence of two such features: communicative intent and a live interlocutor. Four structural priming experiments contrasted the magnitude of structural alignment between a dialogue situation that involved a joint task and an otherwise identical monologue situation that lacked a communicative component. None of the four experiments showed any statistical differences in alignment between dialogue and monologue. Post-hoc analyses on the pooled data of Experiments 2–4 further suggested that individual differences in attention (operationalized through reaction time variability in the picture verification component of the task we used to elicit alignment) might modulate overall structural alignment, and that dialogue (presumably through sustaining attention) might be able to sustain alignment over time to a greater extent than monologue. These results suggest a role for attention in supporting structural alignment, but the lack of clear differences between alignment magnitudes in monologue and dialogue (absent in individual experiments and weak even in the pooled analyses) suggests that communicative intent and a physically-present interlocutor have at best a minor role in promoting alignment.